Job Title: Senior Mechanical Engineer
Location: Either Warrington, Bristol, Newbury or Preston
Compensation: Competitive + Benefits
Role Type: Full time / Permanent
Role ID: SF
At Cavendish Nuclear we’re working to create a safe and secure world, together, and if you join us, you can play your part as a Senior Mechanical Engineer.
The role
As a Senior Mechanical Engineer, you’ll have a role that’s out of the ordinary. This role will contribute to a high-impact public sector Defence Nuclear infrastructure initiative focused on enhancing operational resilience and sustainability across critical systems. The project involves complex mechanical systems integration, requiring innovative engineering solutions within a multidisciplinary team.
Day-to-day, you’ll lead the delivery of complex mechanical engineering tasks, applying deep technical expertise to solve challenging problems, produce and review high-quality documentation, and guide junior engineers, while collaborating across disciplines to ensure project milestones are met with precision and integrity.
1. Foster collaboration across engineering and cross-functional teams to ensure cohesive project delivery and technical alignment.
2. Build and maintain strong relationships with customers, providing clear communication and technical insight to support project progress and business development.
3. Apply relevant procedures, codes, and standards rigorously to all engineering activities, ensuring compliance and technical excellence.
4. Lead the production and review of engineering outputs—including calculations, drawings, models, and reports—while maintaining design integrity throughout the lifecycle.
5. Identify and manage project risks, contribute to safety assessments, and support continuous improvement through technical evaluations and process enhancements.
This role is full time, 37 hours per week provides hybrid working arrangements with 3 days in the office/onsite and 2 days working from home.
Essential experience of the Senior Mechanical Engineer
6. Proven experience delivering engineering activities across the full project lifecycle, from concept design through to implementation.
7. Demonstrated ability to work effectively within multidisciplinary teams, contributing to complex technical solutions and project outcomes.
8. Strong track record of producing and reviewing detailed engineering documentation, including calculations, drawings, and technical reports.
9. Excellent communication skills with the ability to engage confidently with stakeholders and customers to resolve technical and delivery challenges.
Qualifications for the Senior Mechanical Engineer
10. Engineering degree (or equivalent qualification) in relevant engineering discipline, with significant demonstrable experience
Security Clearance
The successful candidate must be able to achieve and maintain Standard (BPSS) / Security Check (SC) security clearance for this role. Further details are available at
What we offer
11. Generous holiday allowance
12. Matched contribution pension scheme, with life assurance
13. Access to a Digital GP, annual health check, and nutritional consultations through Aviva DigiCare+
14. Employee share scheme
15. Employee shopping savings portal
16. Payment of Professional Fees
17. Reservists in the armed forces receive 10-days special paid leave
18. Holiday Trading is a benefit that allows UK Cavendish employees to buy additional leave or to sell up to one working week of annual leave from their annual entitlement. This Window opens February through to March annually.
19. ‘Be Kind Day’ enables employees to take one working day's paid leave a year (or equivalent hours) to undertake volunteering work with their chosen organisation or registered charity
20. Excellent development opportunities and benefits package including an employee assistance programme supporting physical, mental and financial wellbeing.
Cavendish Nuclear
As a leader within the UK nuclear industry, Cavendish Nuclear, part of